diff --git a/lib/httparty/request.rb b/lib/httparty/request.rb
index 84eb5d7..b869625 100644
--- a/lib/httparty/request.rb
+++ b/lib/httparty/request.rb
@@ -1,8 +1,10 @@
 require 'uri'
 
 module HTTParty
+
   class Request #:nodoc:
     SupportedHTTPMethods = [Net::HTTP::Get, Net::HTTP::Post, Net::HTTP::Put, Net::HTTP::Delete]
+    SupportedURISchemes  = [URI::HTTP, URI::HTTPS]
 
     attr_accessor :http_method, :path, :options
 
@@ -27,6 +29,10 @@ module HTTParty
         new_uri.query = query_string(new_uri)
       end
 
+      unless SupportedURISchemes.include? new_uri.class
+        raise ArgumentError, "Cannot parse '#{new_uri}' as a supported URI class"
+      end
+
       new_uri
     end